Multi-colored
Calsilica some times called Rainbow Calsilica has an interesting history
as its origin have been discussed, since it was first introduced into the jewelry
trade, as to it being natural or man made. The legend has it being mined
in Mexico, and that's when the debate started as to its real origins. The
paragraph above shows it as a man made material but one that still has a
lot of appeal to consumers and collectors.

"Rainbow
Calsilica is an artificial material created for carving and lapidary purposes. It
contains a mixture of calcite, plastic and artificial coloring pigments
(PB15, an art-supply pigment), and a paraffin-like material. [ref: Winter
2002, Gems and Gemology, journal of Gemological Institute of America].

Although suppliers claim it to be a natural stone, tests have indicated
that it is probably powdered carbonate rock artificially colored and then
stabilized with plastic. Never the less it is still very, very
....BEAUTIFUL.